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Assertion (A) : If f(x)=logx," then "f(x...

Assertion (A) : If `f(x)=logx," then "f(x)gt0" for all "xgt0`.
Reaosn (R) : `f(x)=logx,` is defined for all `xgt0`

A

Both A and R are individually true, and R is the correct explanation of A

B

Both A and R are individually true but R is not the correct explanation of A.

C

A is true but R is false.

D

A is false but R is true.

Text Solution

Verified by Experts

The correct Answer is:
D
(A):f(x)=logx for x=1, f(x)=log 1=0 (R):f(x)=log x
and `f(x)ge0AAxgt0`
Thus, (A) is false but (R) is true.
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NDA PREVIOUS YEARS-FUNCTIONS, LIMIT, CONTINUITY AND DIFFERENTIABILITY-MCQs
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